EP2609178A1

EP2609178A1 - Ester oils

Info

Publication number: EP2609178A1
Application number: EP11754976.6A
Authority: EP
Inventors: Patrick LÄMMLE; Bernardo Walterspiel; Mathias Woydt
Original assignee: PANOLIN Holding AG
Current assignee: PANOLIN Holding AG
Priority date: 2010-08-25
Filing date: 2011-08-25
Publication date: 2013-07-03
Also published as: BR112013004432A2; US20130190217A1; CH703629A8; CH703629A2; WO2012024808A1; CA2809150A1

Abstract

According to a first aspect, an ester oil, in particular for producing a hydraulic fluid and/or a lubricant, containing an esterification product from the esterification of at least one monoalcohol with at least one polycarboxylic acid, is characterized in that the monoalcohol and/or the polycarboxylic acid originates from renewable raw materials. According to a second aspect, an ester oil, in particular for producing a hydraulic fluid and/or a lubricant, containing an esterification product from the esterification of at least one monocarboxylic acid with at least one dialcohol, is characterized in that the dialcohol and/or the monocarboxylic acid originates from renewable raw materials.

Description

Esteröle

Technical area

The invention relates to ester oil, in particular for producing a hydraulic oil and / or a lubricant, comprising an esterification product of at least one monoalcohol with at least one multiple carboxylic acid. Furthermore, the invention relates to an ester oil, in particular for producing a hydraulic oil and / or a lubricant, comprising an esterification product of at least one monocarboxylic acid with at least one dialcohol. In addition, the invention relates to processes for the preparation of ester oils and the use of ester oils. State of the art

Lubricants or lubricants are used in particular for friction and wear reduction, for corrosion protection, for sealing, for cooling, as well as for vibration damping or power transmission in mechanical systems. Depending on the intended application lubricants are used in solid, liquid or gaseous state.

In particular, liquid lubricants are widely used in various technical fields and are used, inter alia, as engine oils, turbine oils; Hydraulic fluids or gear oils. One known class of liquid lubricating oils are ester-based lubricating oils containing as main component organic reaction products of carboxylic acids with alcohols. The demands on modern ester oils are manifold. For example, an ester oil must satisfy the requirements imposed by the intended application in terms of density, viscosity, viscosity index, pour point, yield point, flash point, seal compatibility, aging resistance, toxicity and / or biodegradability.

DE 10 2006 001 768 (Cognis) describes z. B. esters based on branched Guerbet alcohols as a lubricant and carrier medium for hydraulic fluids. The esters with branched alcohols can also be produced from renewable raw materials.

The subject of DE 10 2004 034 202 (SASOL) are ester mixtures, eg. B. as hydraulic oils, consisting of the reaction product of a branched alcohol with a multiple carboxylic acid. Branched alcohols in particular 2-alkyl-branched alcohols are mentioned, which are preferably Guerbet alcohols. Renewable resources are not mentioned.

DE 10 2006 027 602 (Cognis) describes lubricants, for example gear, industrial and engine oils and hydraulic oils. The base oils are in the form of mixtures Hydrocarbons (mineral oil, PAOs) with high-viscosity esters (HVE) before, which also have additives to improve the viscosity index. Reaction products of carboxylic acids and alcohols are disclosed. These do not come from renewable raw materials. However, known esters are comparatively complicated to produce and correspondingly less economical.

Although ester oils have been known for some time, the economical and environmentally compatible production of optimized and flexible ester oils is still a major challenge. Presentation of the invention

The object of the invention is to provide an ester oil belonging to the technical field mentioned at the outset which is as cost-effective and environmentally compatible as possible and, in particular, has optimum properties for applications as a lubricating oil. A first solution of the problem is defined by the features of claims 1 and 41.

A first aspect of the invention relates to ester oil, in particular for producing a hydraulic oil and / or lubricant, comprising an esterification product of at least one monoalcohol with at least one polycarboxylic acid, wherein the monoalcohol and / or the polycarboxylic acid originate from renewable raw materials. In a process for producing such an ester oil, in particular for use in a hydraulic oil and / or a lubricant, a monoalcohol is reacted with a polycarboxylic acid to form an ester oil, wherein the monoalcohol and / or the polycarboxylic acid are derived from renewable resources.

In principle, the monoalcohol and / or the polycarboxylic acid can also be derived from mixtures of renewable and fossil raw materials. It is therefore not mandatory for the monoalcohol and / or the polycarboxylic acid to consist exclusively of .

4 renewable raw materials. In a preferred variant, however, the monoalcohol and / or the polycarboxylic acid are derived essentially exclusively from renewable raw materials.

In this context, a renewable raw material or a renewable raw material is understood in particular to mean an organic compound which is obtained by direct isolation and / or by refinement from organic raw materials, the organic raw materials being taken primarily from the living nature. Suitable organic raw materials are, for example, plants. Renewable resources are not to be confused with non-renewable raw materials from fossil sources. The latter are z. B. Degradation products of dead plants and / or animals whose formation takes place in geological or astronomical time periods, that is, has started well over 60Ό00 years ago.

Renewable raw materials can be distinguished from non-renewable raw materials from fossil sources, in particular by the proportion of the radioactive ^u C carbon isotope in the raw material. Due to their age, raw materials from fossil sources have essentially no ¹⁴ C carbon isotopes, while renewable raw materials have a characteristic fraction of the ^uC carbon isotope. ^u C-carbon isotopes are constantly formed by nuclear reactions in the upper Earth's atmosphere and enter the biosphere via the carbon cycle. There is essentially a balance between new formation and permanent radioactive decay. Accordingly, in living organisms of the biosphere (plants, animals) in about the same distribution ratio of radioactive carbon ( ¹⁴ C) to non-radioactive carbon ( ¹² C and ³ C), as it is present in the atmosphere. The novel ester oils, based on the carbon fraction, are preferably at least 25 mol%, more preferably at least 50 mol%, even more preferably at least 60 mol%, particularly preferably at least 70 mol% formed from renewable raw materials. Lubricants with a minimum content of 25 mol% of the total formulation of renewable raw materials (nwR) are referred to in Europe as Biolubes. With further eco-labels lubricants are awarded if, based on the carbon content, preferably at least 50 mol%, more preferably at least 60 Mol%, particularly preferably at least 70 mol% consist of renewable raw materials. In both cases, criteria relating to toxicology must also be met. In other regions, other criteria must be taken into account. For example, the term "Biopreferred", which is known in the USA, requires certain proportions of renewable raw materials, but no statements are made about their toxicity.

The radiocarbon method used to determine the proportion of ¹ C carbon isotopes is well known to those skilled in the art (ASTM D6866 or DIN EN 15440). The chemically treated samples are z. B. by Libby's counting tube method, by liquid scintillation spectrometry and / or by mass spectrometric detection in accelerators. It is also possible to take account of short-term and long-term fluctuations in the production of ¹ C carbon isotopes in the course of geological history.

A particularly suitable and standardized method for determining the proportion of renewable resources in a product to be tested is z. As defined in the standard ASTM D6866-08. The organic content of the product derived from renewable raw materials shall be determined in relation to the total organic content of the product. Inorganic carbon and substances without carbon content are not taken into account. The method is based on liquid scintillation spectrometry. The measured ratio of ¹⁴ C to ¹² C in the product to be tested is determined relative to a standard compound (oxalic acid).

The term lubricant is to be understood in particular to mean an intermediate which serves to reduce friction and wear, as well as for power transmission, cooling, vibration damping, sealing action and / or for corrosion protection. In particular, the lubricant of interest in this context is a fluid. A specific lubricant is z. B. a hydraulic fluid. A hydraulic fluid is in particular a fluid which can be used for the transmission of energy (volume flow, pressure) in a hydraulic system. Preferably, the hydraulic fluid is a hydraulic oil, which in particular is not miscible with water. As has been found, the novel ester oils according to the first aspect, in which the monoalcohol and / or the polycarboxylic acid originate from renewable raw materials, are particularly advantageous. On the one hand, such ester oils have advantageous properties with regard to use as lubricants and hydraulic oils. In particular, such ester oils also have good lubricating properties and a high Luftabscheidevermögen. It has also been found that the ester oils have a long life or aging resistance compared with known lubricating oils.

Furthermore, the inventive ester oils have a high flash point, so that even use at higher oil sump and component temperatures is safely possible. In addition, the flow limit (pour point) of the ester oils is relatively low, as a result of which the ester oils can also be used at low temperatures. The flow limit for a liquid product indicates the temperature at which it is just still able to flow when cooled. Thus, the inventive ester oils can be used in a wide temperature range.

The viscosity of the novel ester oils is also in an optimum range for lubricating oils and hydraulic fluids. An adjustment of the viscosity by mixing with another, for. B. thicker, oil is not required. Thus, the inventive ester oils can be used even at elevated temperatures without causing viscosity changes in the ester oil, as is the case with blended oils due to the different evaporation properties of the individual oil components.

Even a most disadvantageous addition of viscosity-modifying thickeners is not required in the novel ester oils due to the relatively high viscosity. The Luftabscheidevermögen the ester oils is thus not impaired and the problem of softening of seals, eg. B. in hydraulic systems, turns scarcely with the novel ester oils.

Further, the viscosity index (VI), which characterizes the temperature dependence of the kinematic viscosity of a lubricating oil, in the inventive Ester oils relatively high. Thus, the ester oils thus show a relatively small temperature-dependent viscosity change, which is very advantageous for most applications in practice, since they can be used in a wide temperature range with relatively constant properties. As has been shown, the evaporation losses (NOACK) of the ester oils according to the invention are also relatively low.

In addition, the use of renewable resources allows a particularly environmentally friendly and economical production. In particular, through the use of renewable raw materials, the inventive ester oils are able to convince at the same time in terms of toxicology and biodegradability. Essentially, the ester oils according to the invention have a relatively rapid and easy biodegradability.

The combination of the inventive chemical structure and the use of renewable raw materials thus allows an unexpectedly economical production of ester oils, which have surprisingly advantageous properties as lubricants.

Advantageously, the multiple carboxylic acid is derived from renewable raw materials. This has proved to be advantageous, in particular with regard to the economic efficiency of the production. In particular, the polycarboxylic acid can be prepared from vegetable oils which are already available worldwide in large quantities. From renewable raw materials or vegetable oils can also be a variety of different polycarboxylic acids win in relatively simple chemical process steps. In addition, compliance with current environmental regulations or labels is made possible. But it is also possible in principle, for. B. from fossil raw materials synthesized multiple carboxylic acid, if appropriate.

Preferably, the polycarboxylic acid is saturated. In other words, preferably only single bonds are present between the carbon atoms of the polycarboxylic acid. As Ester oils with such polycarboxylic acids have been found to be particularly resistant to oxidation and more stable, which benefits the life or aging resistance of the ester oils.

However, it may be possible to use mono- or polyunsaturated polycarboxylic acids for specific purposes.

In a further preferred variant, the polycarboxylic acid is unbranched. In other words, the polycarboxylic acid preferably has an unbranched carbon chain, which is in particular linear. This has proven to be advantageous for a variety of applications. In another and likewise advantageous variant, however, the polycarboxylic acid may also be branched. Whether an unbranched or a branched polycarboxylic acid is more advantageous depends inter alia on the monoalcohols used for the ester oil and the desired material properties of the ester oil. The use of branched polycarboxylic acids may lower the yield point and increase the flash point, which may be advantageous for specific applications. In addition, ester oils with branched polycarboxylic acids may have higher seal compatibilities. Below, in the context of monoalcohols, this aspect will be discussed in more detail. Preferably, the polycarboxylic acid has 6 to 13 carbon atoms, more preferably 8 to 13 carbon atoms. On the one hand, such polycarboxylic acids can be economically obtained from renewable raw materials and, on the other hand, enable the production of a wide range of ester oils which are particularly suitable as lubricants or hydraulic oils. In principle, however, it is also possible to provide polycarboxylic acids having less than 6 or more than 13 carbon atoms. Depending on the desired properties of the ester oils, this may even be advantageous. Most preferably, the polycarboxylic acid comprises a dicarboxylic acid. This can be combined with monoalcohols form dicarboxylic acid, which are particularly suitable as lubricants and hydraulic oils. In addition, the production of dicarboxylic acids from renewable raw materials, eg. As vegetable oils, easily possible, which is beneficial to the economy.

In principle, however, other polycarboxylic acids, for. As tricarboxylic acids are used.

Advantageously, the dicarboxylic acid comprises in particular adipic acid (1,6-hexanedioic acid, HOOC-C ₄ H ₈ -COOH), suberic acid (octanedioic acid, HOOC-C ₆ H ₁₂ -COOH), azelaic acid (nonanedioic acid, HOOC-C ₇ H _u -COOH) , Sebacic acid (decanedioic acid, HOOC-C ₈ H ₁₆ -COOH), dodecanedioic acid (HOOC-C ₁₀ H ₂₀ -COOH) and / or brassylic acid (HOOC-CiiH ₂₂ -COOH). These unbranched dicarboxylic acids with 6, 8, 9, 10, 12 or 13 carbon atoms can be produced from renewable raw materials or vegetable oils. In addition, with these dicarboxylic acids with a variety of recoverable from renewable raw materials monoalcohols for lubricants or hydraulic oils suitable ester oils can be produced.

In principle, however, it is also conceivable to use polycarboxylic acids with three or even more carboxylic acid groups. Also, other than the above representatives of dicarboxylic acids can be used which z. B. less than 6 carbon atoms or more than 13 carbon atoms. For example, branched derivatives of adipic acid, suberic acid, azelaic acid, dodecanedioic acid and / or brassylic acid can be used. In particular, these are methyl-branched derivatives, such as. B. trimethyladipic acid.

It may also be advantageous to provide a mixture of at least two different polycarboxylic acids. In this case, on the one hand, the properties of the ester oils can be controlled even more precisely and, on the other hand, the production process can be further optimized with regard to economic efficiency. Advantageously, the at least two different polycarboxylic acids originate from renewable raw materials. In a further optional variant, the polycarboxylic acid is a cyclic polycarboxylic acid, in particular a cyclic dicarboxylic acid, more preferably 1,2-cyclohexanedicarboxylic acid [CAS * 2305-32-0; C ₈ H ₁₂ O ₄ ; M _w = 172.2] and / or 1, 4-cyclohexanedicarboxylic acid [CAS #: 61-82-9; C ₈ H ₁₂ O ₄ ; M _w = 172.2]. In particular, the at least one monoalcohol originates from renewable raw materials. Thus, the inventive ester oils can be produced particularly economically by fatty acids from vegetable oils. A variety of different monoalcohols can be obtained oleochemically from fatty acids by known chemical reactions. Since in each case at least two moles of monoalcohol per mole of polycarboxylic acid can be reacted, a relatively high proportion of renewable raw materials in the reaction product or the ester oil can be achieved by the use of monoalcohols from renewable raw materials. This also simplifies compliance with current environmental regulations or environmental labels. Particularly preferably, both the polycarboxylic acid and the monoalcohols originate from renewable raw materials. Thereby, the above-mentioned advantages can be further improved.

However, it is also possible in principle to use monoalcohols from fossil raw materials, if this appears expedient. Preferably, the at least one monoalcohol is saturated. In other words, preferably only single bonds are present between the carbon atoms of the at least one monoalcohol. Thus, in particular, the oxidation resistance and stability of the ester oil can be improved.

In a particularly advantageous variant, both the polycarboxylic acid and the at least one monoalcohol are saturated. As a result, the oxidation and aging resistance can be greatly improved.

In principle, however, the at least one monoalcohol may also be monounsaturated or polyunsaturated. Advantageously, the at least one monoalcohol is unbranched. Thus, the at least one monoalcohol advantageously has an unbranched carbon chain, which in particular is linear. The monoalcohol is also referred to in this case as n-monoalcohol. This has proven to be advantageous for a variety of applications. This is especially true when combined with unbranched polycarboxylic acids and especially with unbranched dicarboxylic acids.

In another advantageous variant, however, the at least one monoalcohol may also be branched. The use of branched monoalcohols may lower the yield point and increase the flash point, which may be advantageous for specific applications. In addition, ester oils with branched monoalcohols may have higher seal compatibilities.

Branched monoalcohols have proved advantageous, in particular in combination with unbranched polycarboxylic acids and in particular unbranched dicarboxylic acids. Branched polycarboxylic acids, in particular branched dicarboxylic acids, are advantageously used in combination with unbranched monoalcohols.

In principle, however, it is also possible to use branched monoalcohols in combination with branched polycarboxylic acids.

Branched monoalcohols advantageously have an iso-end branching. This means, in particular, that a methyl group is arranged or branched off at the second position of the end of the carbon chain remote from the alcohol group. Ester oils comprising monoalcohols with terminal iso branches have proven to be advantageous in practice, in particular for lubricants and hydraulic oils, and at the same time can be produced relatively inexpensively from renewable raw materials.

In principle, also branched monoalcohols can be used. However, this may result in ester oils which are expensive and expensive to produce and / or are less suitable for lubricants or hydraulic oils.

Particularly advantageously, the at least one monoalcohol has 6-24, preferably 8-16, carbon atoms. Particularly preferably, the at least one monoalcohol 9, 1 1, 12, 14 and / or 16 carbon atoms. On the one hand, such monoalcohols can be obtained economically from renewable raw materials and, on the other hand, enable the production of a wide range of ester oils which are particularly suitable as lubricants or hydraulic oils. This especially in combination with a multiple carboxylic acid or a dicarboxylic acid having 6 to 13 carbon atoms.

In principle, it is also possible to provide monoalcohols having less than 6 or more than 16 carbon atoms. Depending on the desired properties of the ester oils, this may also be advantageous under certain circumstances.

Advantageously, the at least one monoalcohol is a fatty alcohol and in particular an unbranched fatty alcohol from the group 2-octanol (C ₈ H ₁₈ 0), 1-nonanol (C ₉ H ₂₀ O), 1-undecanol (C ^ Hz ^), 1- Dodecanol (C ₁₂ H ₂₆ O), 1-tetradecanol (C _u H ₃₀ O) and / or cetyl alcohol (also known as 1-hexadecanol; C ₁₆ H ₃₄ 0). Such monoalcohols are particularly economically available from renewable raw materials and particularly suitable for the novel ester oils. It may also be advantageous to use mixtures of two or even more different fatty alcohols. Such mixtures are also referred to as cuts.

Fatty alcohols are commonly available as blends or cuts of different carbon chain lengths. In the present case, the following cuts are particularly suitable: C8 - C10 fatty alcohols and / or C16 - C18 fatty alcohols. From these, for example, the following ester products can be formed: di-alkyl (C8-10) nonanedioate [CAS #: 92969-93-2], di-alkyl (C16-18) nonanedioate [CAS * 92969-94-3], mono- alkyl (C8-10) nonanedioate [CAS * 92969-95-4] and / or monoalkyl (C16-18) nonanedioate [CAS *: 92969-96-5].

In a further advantageous variant, the at least one monoalcohol comprises methyltetradecanol (13-methyl-1-tetradecanol; C ₁₅ H ₃₃ 0). This is a saturated iso-end-branched monoalcohol.

The monoalcohols mentioned in the last two paragraphs have been found to be particularly advantageous in combination with polycarboxylic acids, in particular dicarboxylic acids having 6 to 13 carbon atoms, more preferably 8 to 13 carbon atoms proved. Particularly suitable are combinations with adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid and / or brassylic acid.

However, other alcohols and / or combinations with other polycarboxylic acids are also possible in principle. The polycarboxylic acid is particularly preferably a dicarboxylic acid having 12 carbon atoms, in particular 1, 12-dodecanedioic acid, and the at least one monoalcohol is an alcohol having 13 carbon atoms, more preferably 1-tridecanol and / or isotridecanol. Such ester oils have proven to be particularly advantageous for lubricants and hydraulic oils in terms of preparation and properties. The esterification product of the dicarboxylic acid dodecanedioic acid and the monoalcohol isotridecanol has proved particularly suitable in connection with lubricants and / or hydraulic oils. The resulting di-Isotridecyldodekandioat [C ₃₈ H ₇₄ 0 ₄ ; M _w = 595.0] is particularly convincing in terms of viscometric properties (NOACK value) and flash point and has already as unadditiviertes base oil over known fully-formulated lubricants significant advantages (see also Tables 2 and 3).

Depending on the application, however, other ester oils according to the invention may also be more advantageous.

Another solution of the inventive task is defined by the features of claims 18 and 42.

A second aspect of the invention relates to an ester oil, in particular for producing a hydraulic oil and / or a lubricant, comprising an esterification product of at least one monocarboxylic acid with at least one dialcohol, wherein the dialcohol and / or monocarboxylic acid originate from renewable raw materials. In a method for producing such an ester oil, in particular for use in a hydraulic oil and / or a lubricant, a dialcohol with a monocarboxylic acid converted to an ester oil, wherein the dialcohol and / or the monocarboxylic acid derived from renewable resources.

In principle, dialcohol and / or the monocarboxylic acid can also be derived from mixtures of renewable and fossil raw materials. It is therefore not mandatory that the dialcohol and / or the monocarboxylic acid originate exclusively from renewable raw materials. In a preferred variant, however, the dialcohol and / or monocarboxylic acid are derived essentially exclusively from renewable raw materials.

Under a dialcohol is understood in this context, in particular an organic compound having exactly two hydroxyl groups. Dialcohols may also be referred to as diols and / or dihydric alcohols.

The novel ester oils according to the second aspect have proven to be unexpectedly advantageous. In particular, such ester oils are suitable for lubricants and hydraulic oils. Thus, the ester oils also have good lubricating properties and a high Luftabscheidevermögen. It has also been found that the ester oils have a long life or aging resistance compared with known lubricating oils.

Furthermore, the inventive ester oils have a high flash point, so that use at higher temperatures is also possible without risk. In addition, the flow limit of the ester oils is relatively low, whereby the ester oils can be used even at low temperatures. Thus, the inventive ester oils can be used in a wide temperature range.

The viscosity of the novel ester oils is also in an optimum range for lubricating oils and hydraulic fluids. An adjustment of the viscosity by mixing with another, for. B. thicker, oil is not required. Thus, the inventive ester oils can be used even at elevated temperatures without causing viscosity changes in the ester oil, as is the case with blended oils due to the different evaporation properties of the individual oil components. Even a most disadvantageous addition of viscosity modifying thickeners is not required in the novel ester oils due to the relatively high viscosity and the high viscosity index (VI), which characterizes the temperature dependence of the kinematic viscosity of a lubricating oil. The Luftabscheidevermögen the ester oils is thus not affected, since emulsified air bubbles in the ester oil can be easily separated. Furthermore, the problem of softening of seals, z. B. in hydraulic systems, with the novel ester oils hardly.

Due to the relatively high viscosity index (VI), the ester oils exhibit a relatively small temperature-dependent change in viscosity, which is very advantageous for most applications, since they can be used in a broad temperature range with relatively constant properties.

As has been shown, the evaporation losses (NOACK) of the novel ester oils are also relatively low.

In addition, the use of renewable resources allows a particularly environmentally friendly and economical production. In particular, through the use of renewable raw materials, the inventive ester oils are able to convince at the same time in terms of toxicology and biodegradability. Essentially, the ester oils according to the invention have a relatively rapid and easy biodegradability. In comparison with the ester oils according to the first aspect, monocarboxylic acids are used directly for the preparation of the ester oils in the second aspect of the invention. Monocarboxylic acids are available with a wide variety of structures on the market, with which the properties of the ester oils can be adjusted relatively easily by the use of specific monocarboxylic acids. In addition, fatty acids which are obtainable directly from renewable raw materials or vegetable oils can also be used as monocarboxylic acids. This has proven to be particularly economical.

The dialcohol preferably originates from renewable raw materials. This has proven to be advantageous, in particular with regard to the economic efficiency of the production exposed. Dialcohols can be z. B. in a conventional manner oleochemically produce. For example, a variety of different polycarboxylic acids can be obtained from vegetable oils by oxidative cleavage, which can then be converted by reduction into dialcohols. Corresponding vegetable oils are already available worldwide in large quantities. From renewable raw materials or vegetable oils can thus be obtained in relatively simple chemical process steps, a variety of different polycarboxylic acids, which can be converted to corresponding dialcohols. In addition, compliance with current environmental regulations or labels is made possible. But it is also possible in principle, for. B. use of fossil raw materials petrochemically produced dialcohols, if appropriate.

Preferably, the dialcohol is saturated. In other words, preferably only single bonds are present between the carbon atoms of the dialcohol. Thus, in particular, the oxidation resistance and stability of the ester oil can be improved. In principle, however, the dialcohol can also be monounsaturated or polyunsaturated.

In a further preferred variant, the dialcohol is unbranched. In other words, the dialcohol preferably has an unbranched carbon chain, which in particular is linear. This has proven to be particularly advantageous for a variety of applications of ester oil. In another and likewise advantageous variant, the dialcohol is branched, in particular methyl or branched one or more times. This means in particular that the dialcohol has a carbon chain, from which at least one methyl group (-CH ₃ ) branches off. In particular, the dialcohol z. B. be a trimethylhexanediol (TMH). Together with iso-nonanoic acid results, for example, an esterification product with low temperature viscosities and flow points (η ₁₀ ο · ο ⁼ 4.56 mm ² / s, T oc ⁼ 14,165 mm ² / s (capillary), VI = 123, yield point = -51 ° C. ).

Whether an unbranched or a branched dialcohol is more advantageous depends inter alia on the monocarboxylic acids used for the ester oil and the desired Substance properties of the ester oil from. The use of branched dialcohols may lower the yield point and increase the flash point, which may be advantageous for specific applications. In addition, ester oils with branched dialcohols may have higher seal compatibilities. In particular, methyl branches have proved to be particularly advantageous.

In principle, but instead of or in addition to methyl branches other branches, z. As ethyl and / or Propylverzweigungen possible.

Advantageously, the dialcohol has 5 to 14 carbon atoms. On the one hand, such dialcohols can be economically obtained from renewable raw materials and, on the other hand, enable the production of a wide range of ester oils which are particularly suitable as lubricants or hydraulic oils.

In principle, it is also possible to provide dialcohols having less than 5 or more than 14 carbon atoms. Depending on the desired properties of the ester oils, this can also be advantageous. Most preferably, the dialcohol is a terminal dialcohol. In terminal dialcohols, the alcohol groups are located at the ends of the carbon chain of the alcohol. This can be combined with monocarboxylic acids form ester oils, which are particularly suitable as lubricants and hydraulic oils. In addition, the production of terminal dialcohols from renewable raw materials, eg. As vegetable oils, easily possible, which is beneficial to the economy.

The dialcohol advantageously comprises one or more representatives from the series 1, 6-hexanediol (HO-C ₆ H ₁₂ -OH), 1, 7-heptanediol (HO-C ₇ H _u -OH), 1, 8-octanediol ( HO-C ₈ H ₁₆ -OH), 1, 9-nonanediol (HO-C ₉ H ₁₈ -OH), 1, 10-decanediol (HO-C ₁₀ H ₂₀ -OH), 1, 12-dodecanediol (HO- C ₁₂ H ₂₄ -OH), 1, 13-tridecanediol (HO-C ₁₃ H ₂₆ -OH) and / or their isomers. By isomers are meant, in particular, compounds having the same empirical formula, which, however, differ with regard to linking and / or spatial arrangement of the individual atoms. With such dialcohols having 6, 7, 8, 9, 10, 12 and 13 carbon atoms, a plurality of ester oils can be formed which are can be economically produced from renewable raw materials and which are particularly well suited for lubricants and hydraulic oils.

In principle, it is also conceivable to use alcohols having three or even more hydroxyl groups. Also, other than the above representatives of dialcohols can be used which z. B. less than 5 carbon atoms or more than 14 carbon atoms.

It may also be advantageous to provide a mixture of at least two different dialcohols. In this case, on the one hand, the properties of the ester oils can be controlled even more precisely and, on the other hand, the production process can be further optimized with regard to economic efficiency. Advantageously, the at least two different dialcohols are derived from renewable raw materials.

In a further preferred variant, the at least one monocarboxylic acid originates from renewable raw materials. Thus, the inventive ester oils can be produced, for example, particularly economically in a few process steps via fatty acids from vegetable oils. The fatty acids can be used directly without having to be reacted in additional reaction steps to alcohols or other derivatives. Since in each case at least two moles of monocarboxylic acid per mole of dialcohol can be implemented, a relatively high proportion of renewable raw materials in the reaction product or the ester oil can also be achieved by the use of monocarboxylic acids from renewable raw materials. This also simplifies compliance with current environmental regulations or labels.

Particularly preferably, both the dialcohol and the monocarboxylic acid originate from renewable raw materials. Thereby, the above-mentioned advantages can be further improved. However, it is also possible in principle to use monocarboxylic acids from fossil raw materials, if this appears expedient.

Preferably, the at least one monocarboxylic acid is saturated. In other words, between the carbon atoms of the at least one monocarboxylic acid are preferred only Single bonds before. Thus, in particular, the oxidation resistance and stability of the ester oil can be improved.

In a particularly advantageous variant, both the dialcohol and the at least one monocarboxylic acid are saturated. As a result, the oxidation and aging resistance can be greatly improved.

Advantageously, the at least one monocarboxylic acid is unbranched. Thus, the at least one monocarboxylic acid advantageously has an unbranched carbon chain, which in particular is linear. This has proved to be advantageous, in particular with regard to an optimum viscosity of the ester oil for a large number of applications. This in particular in a combination with unbranched dialcohols.

In another advantageous variant, however, the at least one monocarboxylic acid may also be branched. Particularly suitable are monocarboxylic acids which are methyl-branched one or more times. The monocarboxylic acid particularly preferably has an iso end branching. The use of such branched monocarboxylic acids may under certain circumstances lower the yield point and increase the flash point, which may be advantageous for specific applications. In addition, ester oils with branched monocarboxylic acids may have higher sealing compatibilities.

Branched monocarboxylic acids have proven to be advantageous, in particular in combination with unbranched dialcohols and in particular unbranched dialcohols. Branched dialcohols, in particular branched dialcohols, are advantageously used in combination with unbranched monocarboxylic acids.

In principle, however, it is also possible to use branched monocarboxylic acids in combination with branched dialcohols. In particular, the at least one monocarboxylic acid has 6 to 18 carbon atoms, preferably 9 to 16 carbon atoms. Such monocarboxylic acids can be on the one hand economically recover from renewable resources, eg. B. in the form of fatty acids from vegetable oils, and on the other hand allow the production of a wide range of Ester oils which are particularly suitable as lubricants or hydraulic oils. This especially in combination with dialcohols having 5 to 14 carbon atoms.

In principle, it is also possible to provide monocarboxylic acids having less than 6 or more than 18 carbon atoms. Depending on the desired properties of the ester oils, this may also be advantageous under certain circumstances.

Advantageously, the at least one monocarboxylic acid is a fatty acid and in particular comprises at least one monocarboxylic acid one or more representatives from the set of caprylic acid (C ₇ H ₁₅ -COOH; as octanoic acid hereinafter), pelargonic acid (C ₈ H ₁₇ -COOH; also known as Nonanoic acid), capric acid (C ₉ H ₁₉ -COOH, also referred to as decanoic acid), undecanoic acid (C ₁₀ H ₂ rCOOH), lauric acid (Ο ,, Η ^ -ΟΟΟΗ, also referred to as dodecanoic acid), tridecanoic acid (C ₁₂ H ₂₅ -COOH), myristic acid (C ₁₃ H 27 -COOH, also referred to as tetradecanoic acid), hexanecanoic acid (C ₁₅ H ₃₁ -COOH, also referred to as palmitic acid), octanecanoic acid (C ₁₇ H ₃₅ -COOH, also referred to as stearic acid) and / or their isomers. Such monocarboxylic acids are particularly economically obtainable from renewable raw materials and are particularly suitable for the novel ester oils.

The monocarboxylic acids mentioned in the last paragraph have proved to be advantageous in particular in combination with polyalcohols, in particular dialcohols, with 5-14 carbon atoms. Particularly suitable are combinations with one or more representatives from the series 1, 6-hexanediol, 1, 7-heptanediol, 1, 8-octanediol, 1, 9-nonanediol, 1, 10-decanediol, 1, 12-dodecanediol, 1 , 13-Tridecanediol and / or their isomers.

However, other dialcohols and / or combinations with other polycarboxylic acids are also possible in principle.

In a further optional variant, the monocarboxylic acid is a cyclic monocarboxylic acid, in particular a saturated cyclic monocarboxylic acid. A suitable example is CH3 _(CH2) XC ₆ H ₁₀ - (CH ₂₎ Y-COOH with x + y = 10, particularly preferably 9- (2'-n-propylcyclohexyl) -nonansäure [CH ₃ - (CH ₂₎ ₂ -C ₆ H ₁₀ - (CH ₂ ) ₈ -COOI-I]. This can be obtained directly from linseed oil, which is contained in the seeds of flax, by alkaline isomerization [see Beal et al .; JAOCS 42, 1 1 15 - 1 1 19 (1965)]. The dialcohol is particularly preferably a dialcohol having 12 carbon atoms, in particular 1,12-dodecanediol, and the at least one monocarboxylic acid is a monocarboxylic acid having 13 carbon atoms, more preferably 1-tridecanoic acid and / or isotridecanoic acid. Such ester oils have proven to be particularly advantageous for lubricants and hydraulic oils in terms of preparation and properties.

In both aspects of the invention, the ester oil according to the invention, based on the carbon fraction, is preferably formed from at least 25 mol%, more preferably at least 50 mol%, even more preferably at least 60 mol%, particularly preferably at least 70 mol% from renewable raw materials. In a very particularly preferred embodiment, the inventive ester oil is formed, except for unavoidable impurities, exclusively from renewable raw materials.

This makes it possible to produce for lubricants and hydraulic fluids particularly suitable and powerful ester oils in an economical manner, which are also able to meet current and future environmental regulations.

In principle, less than 25% of renewable raw materials can also be present. However, the aforementioned advantages may be omitted.

As has been shown, a molecular weight of the esterification product is advantageously at least 400 g / mol, in particular at least 550 g / mol. This applies to both inventive aspects. It has been found that such ester oils are particularly suitable, in particular, as lubricants and hydraulic oil. This is probably due to the fact that the substance properties (viscosity, viscosity index, flash point or yield point) which are particularly relevant for lubricants and hydraulic oils in the case of such ester oils are all within a practically optimum to optimum range. However, ester oils having a lower molecular weight than 500 g / mol are also possible. However, this may be detrimental to certain applications of the ester oils.

Preferably, the esterification product has at least 30 carbon atoms and / or at most 50 carbon atoms. As has been shown, arise through Esterification products having at least 30 carbon atoms sufficiently high viscosity values, so that the corresponding ester oils are particularly suitable for hydraulic oil and / or lubricant. The necessity of adding additives to improve the viscosity level can thereby be significantly reduced or even lapses. In addition, it has been found that ester oils containing esterification products having at most 50 carbon atoms with respect to flow properties are particularly suitable for hydraulic oils and / or lubricants. Particularly advantageously, the ester oils contain esterification products having at least 30 carbon atoms and / or at most 50 carbon atoms. This can be in an unexpected way at the same time lower the flow limits and increase the viscosity.

In principle, however, the ester oils may also contain esterification products which have less than 30 carbon atoms and / or more than 50 carbon atoms. This may even be indicated for specific applications.

The novel ester oils can be used in particular as a lubricant and / or hydraulic oil. This applies both to ester oils according to the first aspect and to ester oils according to the second aspect.

Lubricants and / or hydraulic oils which comprise an ester oil according to the invention preferably have a proportion of ester oil of at least 50% by weight, preferably at least 75% by weight, more preferably at least 90% by weight, very particularly preferably at least 93% by weight. %, even more preferably at least 96% by weight, based on the total weight of the lubricant.

Although lower proportions of ester oil are also possible, the lubricants or hydraulic fluid may then no longer have the aforementioned advantageous properties. In a preferred variant, the lubricant and / or the hydraulic fluid contains additives for improving the properties.

Antioxidants, anti-wear additives, metal deactivators, corrosion inhibitors and / or defoamers are advantageously used as additives. As antioxidants in particular aminic antioxidants and / or phenolic antioxidants are advantageous. Suitable aminic antioxidants are alkylated diphenylamines (alkylated DPA) and / or N-phenyl-alpha-naphthylamine (PANA). A proportion of the aminic antioxidants is in particular 0.01-3% by weight, particularly preferably 0.1-0.5% by weight.

In particular, butylhydroxytoluene (BHT), 2,6-di-tert-butyl-phenol (2,6-DTBP) and / or derivatives of 3- (3,5-di-tertiary-butyl-4-hydroxyphenyl) are mentioned as phenolic antioxidants. propionate advantageous. Particularly suitable derivatives are octadecyl 3- (3,5-di-fe / t-butyl-4-hydroxyphenyl) propionate and pentaerythritol tetrakis (3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate for example, 6,6'-di-tert-butyl-2,2'-methylene di-p-cresol [CAS * 1 19-47-1] and 4,4'-methylene-bis-2 are advantageous 6 di-tert-butyl-phenol [CAS *: 1 18-82-1]. A proportion of the phenolic antioxidants is in particular 0.01-5% by weight, particularly preferably 0.3-0.7% by weight.

In particular, the lubricant and / or the hydraulic fluid contain both aminic antioxidants and phenolic antioxidants.

Advantageously, ashless anti-wear additives are used. Wear protection additives such as zinc dithio-phosphates are therefore preferably not used. Suitable anti-wear additives are, in particular, amine phosphates, alkylated phosphates, such as. Tricresyl phosphate, triphenyl phosphorothionate and / or sulfonated esters. A proportion of the anti-wear additives is advantageously 0.01-3% by weight, in particular 0.6-1.0% by weight.

As metal deactivators in particular benzotriazole, tolutriazole and corresponding Mannich bases and / or derivatives of 2,5-dimercapto-1, 3,4-thiadiazole have proven to be advantageous. A proportion of the metal deactivators is advantageously 0.01-1% by weight, preferably 0.02-0.1% by weight.

Suitable corrosion inhibitors are, for example, alkylated succinylic acid and / or derivatives thereof, such as. B. semi-esters, hemiamides and / or amine phosphates. The proportion of corrosion inhibitors is in particular from 0.01 to 3 wt .-%, preferably 0.1 to 0.4 wt .-%. As defoamers are particularly suitable: alkyl polyacrylates, Metaycrylat derivatives and / or polydimethyl-siloxanes (PDMS). An advantageous proportion is 0.001-0.1% by weight, preferably 0.01-0.03% by weight.

The abovementioned antioxidants, anti-wear additives, metal deactivators, corrosion inhibitors and / or defoamers are in particular chemically compatible with the novel ester oils. The stated proportions also provide optimum effects without compromising the performance of the lubricants and / or hydraulic fluids. In principle, however, additional and / or other additives can also be used. It is also possible to dispense with some or all of the additives mentioned.

The monocarboxylic acids, polycarboxylic acids, monoalcohols and / or dialcohols used for the preparation of the ester oils are preferably prepared from fatty acids from renewable raw materials. Particularly suitable are palm oil and / or fatty acids such as oleic acid (C18: 1, 9Z, co-9), linoleic acid (C18: 2, 9Z, 12Z, ω-6), gadoleic acid (C20: 1, 1Z, co-9 ), Erucic acid (C22: 1, 1 3Z, ω-9), petroselinic acid (C 1 8: 1; 6Z; ω-6), arachidonic acid (C20: 4, 51, 8Z, 1 1 Z, 14Z, ω-6 ) and / or generally omega-6 fatty acids. The number following the name of the fatty acid after the letter "C" in parentheses indicates the number of carbon atoms. Separated by a colon, the number of double bonds in the fatty acid and information on the position and configuration (Z, E) of the double bonds in the carbon chain follows. Also listed is the ω-type of the fatty acid or the position of the first double bond relative to the last and of the carboxy group furthest spaced carbon atom ("o") in the carbon chain.

Particularly suitable for the preparation of the monocarboxylic acids, polycarboxylic acids, monoalcohols and / or dialcohols used for the ester oils are also hydroxyfatty acids, in particular ricinoleic acid (C 18: 1; 9Z; 1 2R; 1 2-hydroxy; ω-9), lesquerolic acid (C20: 1 Z 1 1; 14-hydroxy) and / or vernolic acid (C 18: 1; 9Z; 13-epoxy; ω-9). Such sources of raw materials in particular allow an economical production of ester oils for lubricants and hydraulic oils. A variety of vegetable oils and / or animal fats are known to those skilled in the art, from which the fatty acids mentioned above can be obtained. In principle, however, it is also possible to resort to other sources, if this seems more advantageous.

From the following detailed description and the totality of the claims, further advantageous embodiments and feature combinations of the invention result. Brief description of the drawings

The attached drawings show:

Fig. 1 is a diagram showing the friction coefficients (f) as a function of

Time or normal force in a Vibration Scratch Test (according to SRV III and ASTM D 7421-08) for three selected ester oils compared to DITA and TMP;

Fig. 2a, b Four graphs showing the friction coefficient (f), the normal force (F _N ) and deflection (stroke dx) in the vibrational fretting test with diisotridecyl adipate on which Fig. 1 is based, as a function of time; 3a, b Four diagrams showing the coefficient of friction (f), the normal force (F _N ) and deflection (stroke dx) in the vibrational fretting test with di (isotridecyl) dodecanedioate (C12D 13) on which FIG. 1 is based. as a function of time;

4a, b Four diagrams which show the friction coefficient (f), the normal force (F _N ) and deflection (stroke dx) in that of FIG. 1 Vibration Fretting Test with Trimethylolpropane Ester (TMP-C8 / C10) as a function of time.

Ways to carry out the invention

A) Carboxylic acids fatty acids

Fatty acids, such as oleic acid, linoleic acid, gadoleic acid, erucic acid, petroselinic acid, arachidonic acid or generally ω-6-fatty acids can be, for. B. win in a conventional manner via alkaline saponification of the corresponding triacylglycerides. The appropriate fats or oils are boiled with bases. The resulting salts can then be neutralized with acids, whereby free fatty acids or mixtures of free fatty acids are obtained. A separation of the different fatty acids in the mixtures takes place z. B. by a distillative separation process.

Oleic acid may, for. B. from olive oil, peanut oil, avocado oil, goose fat, palm oil, lard, sesame oil, Hammeltalg, beef tallow and sunflower oil are obtained. Linoleic acid is available, for example, from safflower oil, sunflower oil, soybean oil, corn oil and olive oil. Gadoleinic acid is contained in jojoba oil, while erucic acid is found in various types of rapeseed and sea kale. Furthermore, petroselinic acid can be obtained from coriander oil and arachidonic acid from animal fats or fish oil.

Hvdroxyfettsäuren

Rizinolic acid may, for. Example, by hydrolysis of castor oil in which the substance occurs in the form of triglycerides can be obtained. Lesquerolic acid is available, in particular, from the oil of Lesquerella fendleri seeds, while vernolic acid is obtainable by extraction from the seeds of Vernonia galamensis, a plant of the sunflower family.

Adipic acid (C6):

Adipic acid [Chemical Abstracts Number (CAS ^): 124-04-09; HOOC- (CH ₂ ) ₄ -COOH; Molecular weight (M _w ) = 146.14] can petrochemical cyclohexane by double oxidation, z. As with nitric acid, or be obtained from cyclohexanol [K. Saro et al., "A green route to adipic acid: direct oxidation of cyclohexened with 30 percent hydrogen peroxide", Science, Vol. 281, pp. 1646-1647 (1998)]. Also possible is an oxidation of cyclohexene by means of H ₂ O ₂ (30%) over a phase transfer catalyst (quaternary ammonium hydrosulfate or Na ₂ W0 ₂ + CH ₃ (nC ₈ H ₁₇ ) ₃ N] HSO ₄ ). Adipic acid from renewable raw materials can be obtained for example from xylose derivatives (C ₅ sugar), by decarbonylation of furfuryl alcohol (furfural, C ₅ H ₄ 0 ₂ ). It is also possible to obtain from glucose (C ₆ sugar), in the form of sorbitol or from D-glucose [KM Drahts et al., J. Am. Chem. Soc. 1994, Vol. 1 16, pp. 399-400] on cis-cis-muconic acid [CAS-iM 1 19-72-81] and 5-hydroxymethylfurfural (5-HMF) by thermal decomposition from sugar. Furthermore, adipic acid can be obtained via an oxidative cleavage of an ω-6-fatty acid, such as. Gamma-linolenic acid [C ₁₈ H ₃₀ O ₂ ; M _w = 278.43].

In the oxidative cleavage of gamma-linolenic acid as ω-6-fatty acid is obtained 2 mol of adipic acid in addition to 2 mol of malonic acid, which is an effective yield. Also possible is the production of adipic acid by oxidative cleavage of arachidonic acid [CAS # 506-32-1 1; C ₂₀ H ₃₂ O ₂ ; M _w = 304.46]. This can in turn be represented by mono- and disaccharides, hemicellulose (wood boiling), petroselinic acid and / or 1,4-butanediol. Also possible is an enzymatic synthesis of ammonium adipate with genetically modified microorganisms. In this regard, reference is made to US 5,629,190. The Petroselinic Acid [CAS #: 593-39-51, C ₁₈ H ₃₄ 0 ₂ ; M _w = 282.46], an isomer of oleic acid, as a cis- or trans-stereoisomer, has an unsaturated bond at C6, which can be cleaved by oxidation to give adipic acid directly, with lauric acid and n-dodecanoic acid (a C12- monocarboxylic acid;. M _w = 200.31] is obtained latter can then, for example with lithium aluminum hydride, can be reduced to 1-dodecanol. (lauryl alcohol; C ₁₂ H ₂₆ 0 _Mw = 186.33). petroselinic acid itself is contained in the coriander seed, but also in fennel.

Branched adipic acid derivatives (C9)

3-methyladipic acid [CAS * 3058-01-3; C ₇ H ₁₂ O ₄ ; MW = 160.2], a simple methyl branched adipic acid, can be obtained from cresol via methylcyclohexanone and is also commercially available (eg from Sigma-Aldrich).

2,2,3-trimethyl adipic acid [CAS * 28472-18-6; C ₉ H ₁₆ 0 ₄ ; M _w = 188.2], 2,2,4-trimethyl adipic acid [CAS * 3586-39-8; C ₉ H ₁₆ 0 ₄ ; _w = 188.2] and 2,4,4-trimethyladipic acid [CAS * 3937-59-5; C ₉ H ₁₆ 0 ₄ ; M _w - 188.2] are multiple methyl branched derivatives of adipic acid, which are also commercially available. Azeal acid (C9):

Azeal acid [CAS * 123-99-9; C ₉ H ₁₆ 0 ₄ ; with M _w = 188.22] can be obtained by an oxidative cleavage at the double bond of each of oleic acid or cis-9-octadecenoic acid (CAS 12-80-1 * 1; C18: 1 cis-9) by means of ozone (ozonolysis) at ca 100 ° C or the reagents H ₂ O ₂ , NaOCl (with ruthenium catalyst), hot nitric acid, KMnO ₄ or chromic acid. Pelargonic acid (CAS * 1 12-05-0; C ₉ H ₁₈ O ₂ ; with M _w = 158.24, also called nonanoic acid), a monocarboxylic acid, is also obtained as a by-product 5,336.7931. When using elaidic acid or trans-9-octadecenoic acid [CAS * 1 12-79-8; Ci ₈ H ₃₄ 0 ₂ ], which corresponds to the trans isomer of oleic acid, applies mutatis mutandis the same.

The pelargonic acid obtained can be reduced to 1-nonanol [CAS * 143-08-61, M _w = 144.29] as C ₉ -alcohol in order to use it as a regrowing alcohol in a dicarboxylic acid ester.

Azeal acid is also in the same way from gadoleic acid or eicosenoic acid [CAS * 26764-41-0; C20: 1; ω-9; MW - 310.51] obtainable by oxidative cleavage. The by-product is undecanoic acid [CAS * 1 12-37-8; MW = 186.30] as C _n monocarboxylic acid resulting in n-undecanol [CAS #: 1 12-45-2; Ο ,, Η ^ Ο; M _w = 172.30].

Brassylic acid (C13):

Brassylic acid is cis-erucic acid or cis-13-docosenoic acid contained in rapeseed oil, mustard oil or Abyssinian cabbage [CAS #: 1 12-86-7; C22: 1; ω-13; M _w = 338.56] or the trans-isomer trans-13-docosenoic acid. By oxidative cleavage (described in the same manner as in the case of the azealic acid) pelargonic acid is used as monocarboxylic acid and brassylic acid or tridecanedioic acid [CAS * 505-52-2; C ₁₃ H ₂₄ 0 ₄ . M _w = 244.3] as a saturated C ₁₃ dicarboxylic acid formed.

Suberic acid (C8):

Suberic acid can be obtained petrochemically by ozonolysis of cyclooctene. On the basis of renewable raw materials, it can be obtained mainly from cork bark and potato peels.

Cork powder can be split by oxidation with HN0 ₃ to cork acid. Also possible is the oxidative cleavage of ricinoleic acid, palm oil and oleic acid, in which in addition to azelaic also suberic acid is formed, [see, for. BRG Kadesh; J. Am. Oil Chemists' Soc. Vol. 56, pp. 845A-849A (1979) and references therein].

Specifically, suberic acid or octanedioic acid [CAS #: 505-48-6; C ₈ H _u 0 ₄ ; M _w = 174.19] z. B. in a suitable reaction by an oxidative cleavage of the double bond of Ricinoleic acid (CAS #: 141-22-0, 8040-35-5; 17026-54-9; 25607-48-1; 45260-83-1; C18H34O3; M _w = 298.46), a 12-hydroxy-9 octadecenoic acid (C18: 1) from castor oil, available [JW Hill et al., Organic Syntheses, Coli. Vol. 2, p. 53 (1943) and Vol. 56, p. 4 (1933); MJ Diamond et al., J. Am. Oil Chemists' Soc, Vol. 42, pp. 882-884 (1965); RG Kadesh; J. Am. Oil Chemists' Soc. Vol. 31, pp. 568-573 (1954)].

By alkaline cleavage with NaOH at 180-270 ° C to obtain sebacic acid sodium salt and 2-octanol or capryl alcohol [C ₈ H ₁₈ 0; M _w = 130.22]

Dodecanedioic acid (C12)

The Lesquerella seed contains about 55-60% of the hydroxy fatty acid 14-hydroxy-cis-1-eicosanoic acid [CAS * 4103-20-2; C ₂₀ H ₃ ₈ O ₃ ; M _w = 326.51], which is also oxidatively cleavable in NaOH at 180-250 ° C in dodecanedioic acid [C ₁₂ H _Z 2 0 ₄ ] and 2-octanol and 12-hydroxydodecanoic acid [CAS #: 505-95-31] and 2 Octanone [CAS #: 1-1 1-13-7].

B) Preparation of monoalcohols

2-octanol. 1-nonanol. n-undecanol and 1-dodecanol Possible sources and processes for the preparation of 2-octanol [C ₈ H ₁₈ O; M _w = 130.22], 1-nonanol [CAS #: 143-08-61, C ₉ H ₂₀ O; M _w = 144.29], n-undecanol [CAS #: 1 12-45-2; CH ₂₄ 0; M _w = 172.30], 1-dodecanol (lauryl alcohol, C ₁₂ H ₂₆ O, M _w = 186.33) have already been mentioned above in connection with the production of dicarboxylic acids from renewable raw materials. isononanol

3,5,5-trimethylhexyl alcohol or isononyl alcohol [CAS #: 3452-97-9; C ₉ H ₂₀ O; M _w = 144.3], a highly branched isomer of nonanol, is manufactured by EXXON and Kyowa Hakko Kogyo Co. ltd. distributed.

1-decanol 1-decanol [CAS #: 1 12-30-1; C ₁₀ H ₂₂ O; M _w = 158.3] is z. B. by hydrogenation of capric acid (C ₉ H ₁₉ COOH) available. Capric acid itself, for example, comes in Triglycerides bound in vegetable oils and is also contained in palm oil, coconut oil and in the fat of goat's milk.

isodecanol

Isodecanol [CAS * 25399-17-7; C ₁₀ H ₂₂ O; M _w = 158.3] is available, for example under the trade name "EXXAL" about the company Exxon. In addition, mixtures with C 1 -C 4 -alcohols which are rich in C ₁₀ -alcohols are also commercially available [CAS * 93821-1 1-5 or 68526-85-2].

1-tridecanol

1-tridecanol or n-tridecanol [CAS * 1 12-70-9; C ₁₃ H ₂₈ 0; M _w = 200.4] is commercially available with a purity of> 98% (eg from Sigma-Aldrich). However, various mixtures with 1-tridecanol are commercially available. For example, from BASF a mixture of 1-tridekanol with 1-dodecanol [CAS #: 90583-91-8] or Shell under the name "Neodol 25" a mixture of C ₁₀ -C ₁₇ alcohols, which is also the C ₁₃ -Alkohole includes. Also possible for the preparation is the reduction of tridecanoic acid [CAS * 638-53-9; C ₁₃ H ₂₆ 0 ₂ ; M _w = 214.3], which can be found in some vegetable oils (for example in the seeds of the Australian plant Stackhousia tryonii).

isotridecanol

Isotridecanol or 1 1-methyl-dodecanol [CAS * 27458-92-0; C ₁₃ H ₂₈ 0; M _w = 200.4] is available on the basis of propylene tetramer [CAS #: 6842-15-5] or tert-propylene / 1-dodecene [CAS # 1 12-41-4] and via basic oxidation at 250-300 ° C. Commercially sold isotridecanol z. From EXXON under the product name EXXAL13.

1-tetradecanol

1-tetradecanol or myristyl alcohol [CAS * 1 12-72-1; C ₁₄ H ₃₀ O; M _w = 214.4], also commercially defined as a mixture of even and 100% linear C ₁₂ -C ₁₆ -alcohols with> 95% proportion of C _u -alcohols, can be obtained by reduction of myristic acid C ₁₄ : 0 [CAS * 544- 63-81] are obtained, which is contained in coconut oil to about 15 - 21% and in palm kernel oil to about 14 - 18%. General fatty alcohols

It is generally known that fatty alcohols can be obtained directly from vegetable raw materials. Fatty alcohols having 8 carbon atoms (C8) to 18 carbon atoms (C18), such as. For example, 1-octanol [CAS #: 1-1 1-87-5; C ₈ H ₁₈ O], decanol, dodecanol (lauryl alcohol), tetradecanol (myristyl alcohol), hexadecanol (CAS * 36653-82-4, C ₁₆ H ₃₄ 0, M _w = 242.44, also called cetyl alcohol) and / or octanecanol (CAS). #: 1 12-92-5; C ₁₈ H ₃₈ 0; M _w = 270.5; also called stearyl alcohol) can be prepared, for example, by reduction of corresponding esters with sodium (Bouveault-Blanc reaction). Also, fatty alcohols can be prepared by hydrogenation on copper or copper / cadmium catalysts. Frequently, fatty alcohols are produced petrochemically from petroleum today and are accordingly available commercially. From renewable raw materials, fatty alcohols can be prepared in particular by hydrogenation of fatty acids from vegetable oils. The fatty acids are reduced, for example with lithium aluminum hydride in a conventional manner to the corresponding fatty alcohols. C) Preparation of polyols

Neopentylglvkol

Neopentyl glycol or 2,2-dimethyl-1,3-propanediol [CAS * 126-30-7; C ₅ H ₁₂ 0 ₂ ; M _w = 104.2] is commercially available or can be prepared by hydrogenation of the aldol addition product from isobutyraldehyde and formaldehyde (see WO 2008/000650 A1). 1.6-hexane diol:

1, 6-hexanediol [CAS * 629-1 1-8; C ₆ H ₁₄ 0 ₂ ; M _w = 1 18.2] can z. B. by reduction of adipic acid with lithium aluminum hydride or their esters are obtained with elemental sodium. This can be 1, 6-hexanediol produced from renewable resources. Also possible is the preparation of 1,6-hexanediol from glucitol [CAS * 50-70-4; C ₆ H ₁₄ 0 ₆ ; MW = 182.2; also called sorbitol]. Here, glucitol is at positions 2, 3, 4 and 5 reduced with elimination of the hydroxy groups. Glucitol itself is obtainable in a manner known per se by hydrogenation of glucose from cereals, beets or cane sugar.

2.2.4-trimethyl-1,3-pentanediol

2,2,4-trimethyl-1,3-pentanediol [CAS * 144-19-4; C ₈ H ₁₈ 0 ₂ ; M _w = 146.2] is commercially available (Alfa Aesar, Hangzhou Dayang Chemical Co., Ltd.).

2-butyl-2-ethyl-1,3-propanediol

2-butyl-2-ethyl-1,3-propanediol [CAS #: 1-15-84-4; C ₉ H ₂₀ O ₂ ; M _w = 160.3] is also commercially available (Sigma-Aldrich, Jinan Haohua Industry Co., Ltd.).

Further dialcohols From the above dicarboxylic acids can be reduced by reduction, for. B. with lithium aluminum hydride form further dialcohols which can be used for inventive ester oils.

D) refining

The z. B. from the oxidative cleavage of mono- and dicarboxylic acids and alcohols are taking advantage of different material properties such. B. melting point, solubilities (extraction, hot water), boiling temperatures (selective distillation) and / or acid cleavage (H ₂ S0 ₄ ), separated by the skilled person known per se methods to obtain sufficiently pure substances.

E) Preparation of diesters based on dicarboxylic acid esters Dicarboxylic acid esters can be prepared in a manner known per se by reacting dicarboxylic acids with monoalcohols with elimination of water. The esterification can in particular be acid-catalyzed (Fischer esterification) and is well known to the person skilled in the art. In particular, 2 mol of monoalcohols are reacted with 1 mol of dicarboxylic acid for the preparation of dicarboxylic acid esters. The diesters listed in the table below have proven to be particularly advantageous in the field test for hydraulic oils. All diesters can be made from 100% renewable raw materials. In the last column, the maximum proportion of renewable raw materials from the dicarboxylic acid (S) and from the monoalcohols (A) in the diester is indicated in each case.

G) Preparation of ester oils based on diol esters

Dialcohol esters or diol esters can be obtained by reacting dialcohols with monocarboxylic acids. For the preparation of diol esters, in particular 2 mol monocarboxylic acids are reacted with 1 mol of diol.

The diesters listed in the table below have proven to be particularly advantageous in the field test for hydraulic oils. The diol esters can also be produced 100% from renewable raw materials. In the last column, the maximum proportion of renewable raw materials from the diol (A) and from the monocarboxylic acids (S) is indicated in the diol ester.

Diol / diol ester fraction

Monocarbonyric acid

1,6-hexanediol Hexanediol diisodecanoate [C ₂ H ₆ O 5 O ₄ ; M _w = 426.7] A: 23.1% isodecanoic acid S: 76.9%

1,6-hexanediol hexanediol dithiocanate [C ₃₂ H ₆₂ O ₄ ; M _w = 510.8] A: 18.8% 1-tridecanoic acid S: 81.2%

1,6-hexanediol Hexanediol diisotridecanate [C ₃₂ H ₆₂ O ₄ ; M _w = 510.8] A: 18.8% isotridecanoic acid S: 81.2%

1,6-hexanediol hexanediol di-tetradecanate [C ₃₄ H ₆₆ O ₄ ; M _w = 538.9] A: 18% tetradecanoic S: 82%

1, 9-nonanediol Nonandiolditridekanat [C ₃₅ H ₆₈ 0 ₄ ; M _w = 552.9] A: 26% 1-tridecanoic acid S: 74%

1,12-Dodecanediol Dodecanediol dipelargonate [C ₃₀ H ₅₈ O ₄ ; M _w = 482.8] A: 40.0% pelargonic acid S: 60.0% (Nonanoic acid)

1,12-Dodecanediol Dodecanediol diisodecanoate [C ₃₂ H ₆₂ O ₄ ; M _w = 510.8] A: 37.5% isodecanoic acid S: 62.5%

1,12-Dodecanediol Dodecanediol diisotridecanate [C ₃₈ H ₇₄ 0 ₄ ; M _w = 595.0] A: 31.6% isotridecanoic acid S: 68.4%

1, 12-dodecanediol Dodecandiolditridecanat [C ₃₈ H ₇₄ 0 _4; M _w = 595.0] A: 31.6% 1-tridecanoic acid S: 68.4%

The diesters described above are merely examples that may be modified within the scope of the invention.

In the abovementioned adipic acid-based diesters, it is also possible to replace adipic acid with one of the following branched derivatives: 3-methyladipic acid [CAS * 3058-01-3; C ₇ H ₁₂ O ₄ ; M _w = 160.2], 2,2,3-trimethyl adipic acid [CAS #: 28472-18-6; C ₉ H ₁₆ 0 ₄ ; M _w = 188.2], 2,2,4-trimethyl adipic acid [CAS #: 3586-39-8; C ₉ H ₁₆ 0 ₄ ; _w = 188.2] and / or 2,4,4-trimethyladipic acid [CAS #: 3937-59-5; C ₉ H ₁₆ 0 ₄ ; M _w = 188.2]. This can be compared to the unbranched variants lower the flow limits and slightly increase the viscosity.

In the diol esters described above, z. B. 1, 6-hexanediol also be prepared by branched diols from the series neopentyl glycol, 2,2,4-trimethyl-1, 3-pentanediol and / or 2-butyl-2-ethyl-1, 3-propanediol.

H) Hydraulic oils Hydraulic oils according to the invention advantageously have at least 93% by weight of a base oil. For example, a hydraulic oil has the composition described in Table 1 below.

Table 1 : Component proportion [wt .-%]

Amine Antioxidants 0.30

Phenolic antioxidants 0.50

Wear protection additives 0.80

Metal deactivators 0.04

Corrosion inhibitors 0.20

Defoamer 0.02

Ester oil 98.14

(Dicarboxylic acid esters and / or diol esters)

I) Selected diester / viscometric properties

Table 2 below shows various viscometric properties of selected diesters. As can be seen from the table, in particular the diesters having more than 30 carbon atoms have relatively high viscosity layers (compare η ₄₀ · ₍ Γ values), which is particularly advantageous when used as hydraulic oil or lubricant.) The values in the column OECD 301 B / F indicates the biodegradability according to the known OECD-test procedure, in the column UBA- the numbers assigned by the German Federal Environment Agency are given.

Diisotridecyl adipate (C32) 227 8-10 139 -51 27.0 5.4 2362 92 [26401-35-4]

Ditetradecyl adipate (C34) 75 34.3 5.1

[26720-19-4]

azelates

Didecyl azelate (C29)

[2131-27-3]

Di-isodecyl azelate (C29) 230 9.8 151 -65 18.1 4.3 3756

[28472-97-1]

Diundecyl azelate (C31)

Didodecyl azelate (C33)

[26719-99-3]

Bis (2-hexyldecyl) azelate (C41) 278 160 -64 33.0 6.60

Di (isotridecyl) azelate 258 4.0 124 -39 42.4 6.82

[27251-77-0]

Ditridecyl azelate (C35) 243 145 -55 33.8 6.4

[26719-40-4]

Dodecandioate

Dioctyldodecanedioate [42233-97-6]

Diisooctyldodecandioat

[85392-86-5]

Di (iso-C9) dodecanedioate 6.0 184 -25 23.2 5.28 4190

[63003-34-9]

Di (C9) dodecanedioate 245 5.0 189 24.8 5.6

Di (isodecyl) dodecanedioate 266 3.5 161 -46 25.7 5.58

[63003-35-0]

Di (isodecyl) dodecanedioate 4.3 162 -41 23.4 5.2 93

Ditridecyldodecanedioate (C38)

[27742-10-5]

Di (isotridecyl) dodecanedioate 277 5.7 158 -57 42.0 7.5 4203 76 (C38) [84731-63-5]

Dicetyldodecanedioate [42234- 04-8]

diol esters

Dodecanediolipelargonat 7.4 182 -38 25.25 5.58 Hexanediol diisocaprilate (C26) 17.3 1 19 <17.41 3.79

-70

Hexanediol diisomyristate (C34)

J) Comparative experiments with selected diesters

The following are the unadditized ester base oils trimethylolpropane esters (TMP-C8 / C10), diisotridecyl adipate (DITA), di (isotridecyl) dodecanedioate (C12D13, three samples), di (isotridecyl) decandioate (C10D13, three samples), and Di (isotridecyl) nonanedioate (C9D13) and the fully-formulated hydraulic oil "PANOLIN HLP Synth" based on DITA (available from Panolin, Switzerland) are compared in comparison experiments. In addition, the table also contains information on an ester of a diol and two carboxylic acids, namely neopentyl glycol di (isostearate) (D5C 18). The lubricants used have the viscometric properties contained in Table 3. Of the C12D13 esters and the C10D 13 esters, three independently prepared samples were considered. The C9D 13 ester and the D5C18 ester each tested one sample. The columns "CCS- ₂₅ " c [mPas] "and" CCS_ ₂₀ "c [mPas]" contain information from the so-called "Cold Crank Simulator" according to ASTM D5293 at -25 ° C and -20, respectively ° C. The column HTHS [mPas] indicates the so-called "high temperature high shear viscosity" (HTHS) at elevated temperature.

Table 3:

C12D13 0.9020 277 4.3 147 -57 1700 42.0 7.5

(2nd sample)

C12D 13 0.904 261 2.9 156 -51 3'230 41.2 7.6

(3rd sample)

C10D 13 2.7 172 -52 35.5 7.2

(4th sample)

C10D13 250 4 150 -50 36.0 6.8

(5th sample)

C10D13 3.4 149 35.7 6.7

(6th sample)

C9D 13 3.5 150 36.1 6.8

(7th sample)

D5C18 280 2.0 146 -44 46.0 8.0

(8th sample)

DITA 0.91 244 10.0 139 -60 2'646 1 '455 25 5

T P-C8 / 10 0.94 235 3.6 140 -30 853 221 22 4.5

PANOLIN 0.918 240 4.3 146 -57 4'653 2780 47.0 8.10

HLP Synth

Table 4 contains ecotoxicological information for orientation purposes and taken from safety data sheets. The column "Aquatic toxicity [mg / l]" contains information on the toxicity tests according to the known test methods according to OECD 201, 202 and 203.

Table 4:

(2nd sample)

D5C18 85> 1 '000> 1 Ό00> 1 ΟΌ0Ο

(8th sample)

DITA 87> 1 Ό00> 100 2362

TMP-C8 / 10 64-88 140 600> 10Ό00 5371

PANOLIN 67-90

HLP Synth

In Table 3 is particularly positive that the NOACK evaporation (physical evaporation according to Noack, ie 1 h at 250 ° C) in the investigated esters (Sample 1-8) with 2.0 - 4.3% already as a base oil usually much lower precipitated as the ester base oils trimethylolpropane esters (TMP-C8 / C10, 3.6%) and diisotridecyl adipate (DITA 10.0%). Trimethylolpropane esters (TMP-C8 / C10) are commercially available from several suppliers and have been used for comparative purposes.

In addition, the NOACK values of the tested esters are also lower than or equal to the NOACK value of the commercially available hydraulic oil "PANOLIN HLP Synth" (available from Panolin, Switzerland), which is a fully formulated hydraulic oil based on DITA. If one compares the NOACK values of the investigated esters with "PANOLIN HLP Synth", it can be expected that the NOACK value for a hydraulic oil fully formulated from a tested ester will be well below 2.0 - 4.3%. For the environment this means less oil consumption, ie entry into the environment, and less recharging costs for the user, which reduces operating costs and, once again, benefits the environment by conserving resources.

Another advantage of the examined esters is the high flash point of up to 280 ° C, which is about 40 ° higher than that of the "PANOLIN HLP Synth". This is a significant safety gain and additionally opens up the possibility of further increasing the flash point into the area of flame-retardant hydraulic fluids by means of suitable additives.

The C12D 13 base oil is viscometric, so z. B. at the kinematic viscosity at 40 ° C, without the addition of polymeric viscosity index improvers or thickeners, comparable to PANOLIN HLP Synth. This results in a better foam behavior, since the air bubbles are not hindered by the macromolecules on the rise. Furthermore, it can be assumed that the low-temperature viscosities of a polymer-free or polymer-reduced formulation based on C12D 13 are lower. This significantly improves oil penetration at low temperatures. The lubricating film build-up in all lubrication points of the construction machine and its accessories is faster and with lower pump performance (energy efficiency). This reduces the wear in the tribosystems (friction points). This also applies to the other esters studied with shorter carboxylic acids. The C12D13 base oil is classified by the Commission for the Evaluation of Hazardous Substances at the German Federal Environment Agency under the number 4203 in WGK 1 (slightly hazardous to water, WGK = water hazard class), which is a good condition for the formulation of environmentally friendly hydraulic oils.

Overall, the esters studied show higher viscosity indices, increased viscosity levels, increased flash points and also lower NOACK evaporations over diisotridecyl adipate (DITA).

FIG. 1 shows the results of vibrational fretting tests (SRV, model III) with the five unadditized ester base oils diisotridecyl adipate (DITA), trimethylol propane ester (TMP-C8 / C10), di (isotridecyl) nonanedioate (C9D13), di (isotridecyl) dodecanedioate (C12D 13) and di (isotridecyl) decanedioate (C 10D 13).

The test tests were carried out according to the standard ASTM D7421-08 (feeding load) at a typical operating temperature for hydraulic oils of + 80 ° C. The frequency was 50 Hz at a deflection of 1 mm (in the positive x direction) and 2 mm (in the negative x direction). The normal force was increased by 100 N every 2 minutes during the trials. It shows that extending the chain length of the dicarboxylic acid also improves the frying load-bearing capacity of the base oil. For C9D 13, C10D 13 and C12D13, values greater than P 3'938 MPa are reached, as at 2Ό00 N or after 40 minutes, no adhesive failure occurs. The C9D13 diesters and C12D 13 diesters surpass the feeding load limit of the trimethylol propane ester (TMP-C8 / C10) and, even as unadditized base oils, significantly lower the mixing / limiting friction coefficient at high pressures. Noteworthy in these unadditized base oils from C9D13 diesters and C12D13 diesters is the fact that the mixing / limiting friction coefficient is practically invariant to the load increase in the test according to ASTM D7421-08.

Fig. 2a shows graphs showing the coefficient of friction (f) and the normal force (F _N ) (top) and the deflection (stroke dx) and the normal force (F _N ) (bottom) of diisotridecyl adipate in the positive x direction as a function of time represent. Fig. 2b accordingly shows diagrams showing the friction coefficient (f) and the normal force (F _N ) (above) and also the deflection (stroke dx) and the normal force (F _N ) (below) of diisotridecyl adipate in the negative x direction as a function to reflect the time.

Figures 3a, b are graphs showing the corresponding data for diisotridecyl dodecanedioate (C12D13), while Figures 4a, b show in an analogous manner the graphs for trimethylolpropane ester (TMP-C8 / C10).

Particularly noteworthy is the high feeding load of di (isotridecyl) dodecanedioate (C12D13) of> 1700 N after a time of about 42 min (see, for example, Fig. 1). This is extremely high for a base oil, especially at this low viscosity level, and is not achieved by fully formulated lubricants without additional measures. The investigated esters di (isotridecyl) nonanedioate (C9D 13), di (isotridecyl) dodecanedioate (C12D 13) and di (isotridecyl) decanedioate (C10D13) are said to be used for eco-friendly lubricants, preferably at least 25% by weight of carbon Mol%, more preferably at least 50 mol%, even more preferably at least 60 mol%, particularly preferably at least 70 mol% consist of renewable raw materials. For a new class of biolubes it is sufficient if at least 25 mol% of the total formulation consists of renewable raw materials (nwR). Again, the proportion is measured by radiocarbon methods (ASTM D6866 or DIN EN 15440: 201 1-05). This means that the ester C12D13 is already a biolube if only the acid component (dodecanedioic acid, proportion nwR of 31.6%) comes from renewable raw materials. C10D13 (27.8% share nwR) and C9D13 (25.7% share nwR) also meet this criterion. In contrast, C6D13 (DITA, 18.79% nwR) alone can not be considered a biolube. A lubricant based on DITA meets this requirement if it contains additional esters of renewable raw materials in low additions, which can compensate for the proportion of renewable raw materials.

Claims

claims

Ester oil, in particular for producing a hydraulic oil and / or a lubricant, comprising an esterification product of at least one monoalcohol with at least one Mehrfachcarbonsaure, characterized in that the monoalcohol and / or the Mehrfachcarbonsaure derived from renewable raw materials.

Ester oil according to claim 1, characterized in that the Mehrfachcarbonsaure originates from renewable resources.

Ester oil according to any one of claims 1-2, characterized in that the polycarboxylic acid is saturated.

Ester oil according to any one of claims 1-3, characterized in that the polycarboxylic acid is unbranched.

An ester oil according to any one of claims 1 to 3, characterized in that the polycarboxylic acid is branched.

Ester oil according to any one of claims 1-5, characterized in that the polycarboxylic acid has 6 - 13 carbon atoms, preferably 8 - 13 carbon atoms.

7. ester oil according to any one of claims 1-6, characterized in that the Mehrfachcarbonsaure comprises a dicarboxylic acid.

8. Ester oil according to claim 7, characterized in that the dicarboxylic acid contains adipic acid, trimethyladipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid and / or brassylic acid.

9. Ester oil according to any one of claims 1-8, characterized in that the at least one monoalcohol originates from renewable raw materials.

10. Ester oil according to any one of claims 1-9, characterized in that the at least one monoalcohol is saturated.

1 ester oil according to any one of claims 1-10, characterized in that the at least one monoalcohol is unbranched.

12. An ester oil according to any one of claims 1-10, characterized in that the at least one monoalcohol is branched.

13. Ester oil according to claim 12, characterized in that the at least one monoalcohol has an iso-end branching.

14. Ester oil according to any one of claims 1-13, characterized in that the at least one monoalcohol 6-24, preferably 8-16, has carbon atoms, wherein the at least one monoalcohol particularly preferably 9, 1 1, 12, 14 and / or 16 Having carbon atoms.

15. An ester oil according to any one of claims 1-14, characterized in that the at least one monoalcohol is a fatty alcohol.

16. An ester oil according to any one of claims 1-15, characterized in that the at least one monoalcohol 1-nonanol, n-undecanol, 1-dodecanol, 1-tetradecanol and / or cetyl alcohol comprises.

17. ester oil according to any one of claims 1-16, characterized in that the at least one monoalcohol comprises methyltetradecanol.

18. Ester oil, in particular for producing a hydraulic oil and / or a lubricant, comprising an esterification product of at least one monocarboxylic acid with at least one dialcohol, characterized in that the

Dialcohol and / or the monocarboxylic acid derived from renewable resources.

19. Ester oil according to claim 18, characterized in that the dialcohol originates from renewable raw materials.

20. Ester oil according to any one of claims 18 - 19, characterized in that the dialcohol is saturated.

21. Ester oil according to any one of claims 18-20, characterized in that the dialcohol is unbranched.

22. An ester oil according to any one of claims 18-20, characterized in that the dialcohol is branched, in particular methyl branched once or several times.

23. Ester oil according to any one of claims 18-22, characterized in that the dialcohol has 5-14 carbon atoms.

24. ester oil according to any one of claims 18 - 23, characterized in that the dialcohol is a terminal dialcohol.

25. Esteröl according to any one of claims 23 - 24, characterized in that the dialcohol is at least one member selected from pentanediol, hexanediol, heptanediol,

Octanediol, nonanediol, decanediol, dodecanediol, tridecanediol and / or their isomers.

26. Ester oil according to any one of claims 18- 25, characterized in that the at least one monocarboxylic acid originates from renewable raw materials.

27. Ester oil according to any one of claims 18-26, characterized in that the at least one monocarboxylic acid is saturated.

28. An ester oil according to any one of claims 18 - 27, characterized in that the at least one monocarboxylic acid is unbranched.

29. Ester oil according to any one of claims 18 - 27, characterized in that the at least one monocarboxylic acid is branched, in particular methyl or simply methyl branched several times.

30. Ester oil according to claim 29, characterized in that the at least one monocarboxylic acid has an iso-end branching.

31. Esteröl according to any one of claims 18 - 30, characterized in that the at least one monocarboxylic acid 6 - 18 carbon atoms, preferably 9 - has 16 carbon atoms.

32. Ester oil according to any one of claims 18 - 31, characterized in that the at least one monocarboxylic acid is a fatty acid.

33. Ester oil according to any one of claims 18 - 32, characterized in that the at least one monocarboxylic acid comprises caprylic acid, pelargonic acid, capric acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid and / or their isomers.

34. ester oil according to any one of claims 1-33, characterized in that the esterification product based on the carbon content to at least 50 mol%, preferably at least 60 mol%, more preferably at least 70 mol% is formed from renewable raw materials.

35. Ester oil according to any one of claims 1 - 34, characterized in that a molecular weight of the esterification product is at least 400 g / mol, in particular 550 g / mol.

36. Ester oil according to any one of claims 1-35, characterized in that the esterification product has at least 30 carbon atoms and / or at most 50 carbon atoms.

37. Use of an ester oil according to any one of claims 1 - 36 as a lubricant and / or hydraulic oil.

38. Lubricant and / or hydraulic oil containing an ester oil according to one of claims 1 - 36.

39. Lubricant and / or hydraulic oil according to claim 38, characterized in that the proportion of ester oil at least 50 wt .-%, preferably at least 75 wt .-%, more preferably at least 90 wt .-%, of the total weight of the lubricant and / or

Hydraulic oil is.

40. Lubricant and / or hydraulic oil according to any one of claims 38 - 39, characterized in that additives are present, being present as additives antioxidants, anti-wear additives, metal deactivators, corrosion inhibitors and / or defoamers.

41. A process for the preparation of an ester oil, in particular for use in a hydraulic oil and / or a lubricant, wherein a monoalcohol is reacted with a polycarboxylic acid to form an ester oil, characterized the monoalcohol and / or the polycarboxylic acid originate from renewable raw materials.

42. A process for the preparation of an ester oil, in particular for use in a hydraulic oil and / or a lubricant, wherein a dialcohol is reacted with a monocarboxylic acid to form an ester oil, characterized in that the dialcohol and / or monocarboxylic acid originate from renewable raw materials.

43. The method according to any one of claims 41 or 42, characterized in that the alcohols and / or carboxylic acids are prepared from fatty acids from renewable resources.

44. The method according to any one of claims 41-43, characterized in that as fatty acids palm oil, oleic acid C18: 1 (cis-9), linoleic acid (C18: 2, ω-9, ω-12), gadoleic acid (C20: 1 ω -9), erucic acid (C22: 1 ω-9), petroselinic acid (C18: 1, co-6), arachidonic acid and / or ω-6 fatty acids.

45. Process according to one of claims 43-44, characterized in that hydroxy fatty acids, in particular ricinoleic acid (C 18: 1; 9Z; 12R; 12-hydroxy; ω-9), lesquerolic acid (C20: 1; Z 1 1; Hydroxy) and / or vernolic acid (C18: 1; 9Z; 13-epoxy; co-9).